Release/1.9.1

Version 1.9.1 of the module 

- Store category configuration 
- Little fixes
- UI / UX Remodeling 
- Synchronisation of orders from PS to eBay (status)
- Promotional prices (on eBay.co.uk and ebay.de)
- Logs
- Immediat payment

Thoma
You should use Tools::jsonEncode() instead.